(1) Field of the Invention
The present invention relates to a process for machining blade labyrinth seals used on blades. The present invention has particular utility in the manufacture of turbine blades for gas turbine engines.
(2) Background
A seal design has been developed which integrates the seal into the turbine disk and mating turbine blades. This design, sometimes called a labyrinth seal, incorporates a seal located radially at the blade. The challenge is to machine the thin labyrinth form on the turbine blades, without generating any part deflection and meeting all profile and metallurgical requirements.
There is no prior technology which has machined labyrinth features on blades used in gas turbine engines. Wire EDM (electric discharge machining) has been used to machine some blades; however, such a technique generates unacceptable metallurgy. Grinding technology does exist which machines blade root forms, but this technology has not been used to machine such a thin feature which is very susceptible to movement.